A semiconductor light emitting device, such as a light emitting diode (LED) or the like, is a device emitting light through a material contained within the semiconductor light emitting device. LEDs convert energy generated through electron-hole recombination occurring at p-n junctions between p-type and n-type semiconductors into light to be emitted from the LED. Such LEDs have been widely used as light sources in lighting devices, display devices, and the like, and the development of such devices is being accelerated.
In particular, as mobile phone keypads, turn signal lamps, camera flashes and other devices using LEDs (e.g., GaN-based LEDs) are commercialized, the development of general lighting devices using LEDs is being actively undertaken. As the use of LEDs is extended from small portable devices to large, high output, and high efficiency products such as the backlight units of large screen TVs, headlights of vehicles, general lighting devices, and the like, light sources having characteristics required by the corresponding products are being increasingly sought.